
where \(V_{\varphi 100}\equiv V_\varphi /100\,\mathrm {km\,s}^{-1}\) . Since the normalizing constant is not available [1]}, we estimate \(b_0-b_4\)  coupled with the normalizing constant by fitting the PDF to the observed \(V_\varphi \)  distribution. Figure 23 gives an example of the fits for populations with different metallicities. The mean and dispersion are derived by taking the first and second moments of the PDF.
